Карта знаний PHP — huihui-ai:pi-100k, run-97 · think: medium

{"answer": "no", "explanation": "Double-quoted strings interpolate variables and recognize more escape sequences (e.g., \\n, \\t, \\\"), while single-quoted strings only treat \\\\ and \\' specially, so the processing is fundamentally different, not just a speed difference."}

{"answer": "yes", "explanation": "The ?? operator is equivalent to isset($a) ? $a : $b, so it silently returns the fallback without triggering an 'Undefined variable' notice."}

{"answer": "ab", "explanation": "In PHP, echo can take multiple comma-separated arguments and prints them concatenated without any separator, so 'a' and 'b' are printed as 'ab'."}

{"answer": "no", "explanation": "While print does return 1, it is a language construct (not a function), so it cannot be used inside an expression."}

{"answer": "no", "explanation": "The Elvis operator ($a ?: $b) returns the left operand when it is truthy, not falsy; when it is falsy, it returns the right operand."}

{"answer": "yes", "explanation": "In PHP, the concatenation operator (.) has lower precedence than + and -, so expressions like $a + $b . $c are evaluated as ($a + $b) . $c."}

{"answer": "no", "explanation": "The ** operator in PHP is right-associative, so 2 ** 3 ** 2 evaluates as 2 ** (3 ** 2) = 2 ** 9 = 512, not (2 ** 3) ** 2 = 64."}

{"answer": 3, "explanation": "Concatenation (.) has higher precedence than +, so it's parsed as ('sum: ' . 2) + 3, which becomes 'sum: 2' + 3, and since 'sum: 2' is not numeric it evaluates to 0, giving 0 + 3 = 3."}

{"answer": "no", "explanation": "With strict comparison (===), PHP requires arrays to have the same key/value pairs in the same order; order only doesn't matter with loose comparison (==)."}

{"answer": "no", "explanation": "0 == false uses loose (==) comparison and actually returns true, since both 0 and false evaluate to the same falsy value."}

{"answer": "no", "explanation": "In PHP 8, comparing a non-numeric string to an integer falls back to string comparison, so 'abc' == '0' is false (unlike PHP 7 where 'abc' was cast to int 0)."}

{"answer": "yes", "explanation": "In PHP loose comparison (==), null == 0, null == '', and null == false all evaluate to true."}

{"answer": 42, "explanation": "PHP's (int) cast parses the leading numeric portion of the string and ignores the trailing non-numeric characters."}

{"answer": 10, "explanation": "PHP coerces the numeric string '5' to the integer 5, then performs arithmetic addition with 5, yielding 10."}

{"answer": "no", "explanation": "In PHP, casting false to string results in an empty string \"\", not \"0\"; (string)false === \"\"."}

{"answer": "yes", "explanation": "Due to IEEE 754 floating-point arithmetic, 0.1 + 0.2 evaluates to 0.30000000000000004, which is not strictly identical (===) to 0.3."}

{"answer": "no", "explanation": "strrev() reverses a string byte-by-byte, which breaks multi-byte UTF-8 characters; mb_strrev() or similar multi-byte functions are needed for correct UTF-8 reversal."}

{"answer": "yes", "explanation": "The string 'world' is a substring of 'Hello world', so str_returns true."}

{"answer": "no", "explanation": "str_pad() supports STR_PAD_RIGHT, STR_PAD_LEFT, and STR_PAD_BOTH via its $pad_type parameter, not just right-side padding."}

{"answer": "no", "explanation": "By default, trim() strips spaces, tabs, newlines, carriage returns, NUL bytes, and vertical tabs (the character mask is \" \\t\\n\\r\\0\\v\"), not just spaces."}

{"answer": 6, "explanation": "strlen counts bytes; in UTF-8, 'é' is 2 bytes while the other 4 characters are 1 byte each, totaling 6."}

{"answer": "def", "explanation": "substr('abcdef', -3) starts at position -3 (the 3rd character from the end) and returns the remaining characters, which is 'def'."}

{"answer": "no", "explanation": "ucfirst() returns a new string with the first character uppercased; it does not modify the original string in place (PHP strings are passed by value)."}

{"answer": "yes", "explanation": "Heredoc (unlike nowdoc, which uses single quotes) allows variable interpolation; nowdoc treats its content as a literal string with no variable expansion."}

{"answer": "no", "explanation": "PHP's sort() re-indexes the array with sequential integer keys, discarding the original key associations; asort() is the function that preserves them."}

{"answer": "yes", "explanation": "In PHP, string keys that are valid integer representations (like '5') are automatically cast to integer keys when stored in an array."}

{"answer": "no", "explanation": "in_array() defaults to $strict = false, meaning it uses loose comparison (==) unless the third parameter is explicitly set to true."}

{"answer": "yes", "explanation": "Without a callback, array_filter() removes elements considered falsy: 0, 0.0, '', null, false, and '0'."}

{"answer": "no", "explanation": "The $preserve_keys parameter of array_slice() defaults to false, so keys are reindexed by default."}

{"answer": "[20, 30]", "explanation": "array_slice with offset 1 and length 2 extracts elements at index 1 and 2, which are 20 and 30."}

{"answer": 2, "explanation": "Array union (+) keeps left-side values for duplicate keys and adds right-side keys not present on the left, resulting in ['a'=>1, 'b'=>2'] which has 2 elements."}

{"answer": "yes", "explanation": "PHP 8.1 introduced the array spread syntax [...$a, ...$b] which supports both integer and string keys; duplicate string keys are resolved by the later value overwriting the earlier one."}

{"answer": "no", "explanation": "In PHP 8.0+, named arguments and argument unpacking (...$args) can be freely combined in a single function call, e.g. foo(x: 1, ...$args)."}

{"answer": "no", "explanation": "In PHP, a closure must explicitly use the 'use' keyword to capture variables from the outer scope; without it, those variables are not accessible."}

{"answer": 3, "explanation": "func_num_args() returns the total number of arguments passed to the function call, which is 3, regardless of how many parameters are declared in the signature."}

{"answer": "no", "explanation": "An arrow function (fn) in PHP must have a single expression as its body (after =>), not multiple expressions in curly braces; that syntax belongs to regular closures."}

{"answer": "yes", "explanation": "PHP arrow functions (fn) implicitly capture outer variables by value at call time (lazily), so they always see the current value of the variable when invoked, unlike regular closures which capture at definition time."}

{"answer": "yes", "explanation": "In PHP, a static closure (static function() {}) does not bind $this to the enclosing scope, so $this is unavailable inside it."}

{"answer": 5, "explanation": "The use ($x) clause captures the value of $x (5) by value at closure creation time, so later reassigning $x to 7 does not affect the closure."}

{"answer": "yes", "explanation": "In PHP's default weak typing mode, the string '5' is automatically coerced to the integer 5 when passed to an int-typed parameter."}

{"answer": "yes", "explanation": "Constructor property promotion was introduced in PHP 8.0, allowing parameters in __construct to be promoted to properties by adding a visibility modifier and type directly in the parameter list."}

{"answer": "final", "explanation": "In PHP, the 'final' keyword before a method declaration prevents it from being overridden in subclasses."}

{"answer": "yes", "explanation": "In PHP, the final keyword prevents a method from being overridden in any subclass."}

{"answer": "no", "explanation": "In PHP, private properties are only accessible within the class that defines them; subclasses cannot access them (that would require 'protected' visibility)."}

{"answer": "class@anonymous", "explanation": "In PHP, get_class(new class {}) returns a generated name in the format 'class@anonymous' followed by a NUL byte and the file path/line number; the part before the NUL byte is 'class@anonymous'."}

{"answer": "yes", "explanation": "In PHP, private methods are completely hidden from child classes, so a child can freely declare a same-named method with any visibility without it being treated as an override."}

{"answer": "no", "explanation": "__get() is also called when reading inaccessible (protected or private) properties that do exist, not just non-existent ones."}

{"answer": "Error", "explanation": "In PHP, reassigning a readonly property after initialization throws an instance of Error (not Exception)."}

{"answer": "yes", "explanation": "PHP interfaces allow the declaration of public constants, which can be accessed by any implementing class."}

{"answer": "instanceof", "explanation": "The instanceof operator in PHP checks whether an object is an instance of a specific class or interface."}

{"answer": "yes", "explanation": "PHP interfaces can declare static methods; implementing classes are not required to implement them."}

{"answer": "no", "explanation": "PHP's instanceof operator checks both class inheritance and interface implementation; an object is considered an instance of any interface it implements."}

{"answer": "no", "explanation": "In PHP, interface methods are always abstract (no implementation body); only traits (and abstract classes) provide default method implementations."}

{"answer": "yes", "explanation": "In PHP, abstract methods can be declared with public, protected, or (since 7.1) private visibility, so protected is perfectly valid."}

{"answer": 3, "explanation": "Foo::cases() returns an array containing all enum cases, which are A, B, and C — three elements in total."}

{"answer": "yes", "explanation": "PHP traits are allowed to declare constants, just as they can declare methods and (with restrictions) properties."}

{"answer": "yes", "explanation": "In PHP 7+, both Exception and Error implement the Throwable interface, making it their common ancestor in the type hierarchy."}

{"answer": "no", "explanation": "TypeError extends Error, not Exception; both Exception and Error are separate branches under the Throwable interface, so catch(Exception) does not catch TypeError."}

{"answer": "no", "explanation": "The @ operator only suppresses errors/warnings/notices, not exceptions; exceptions must still be caught with try/catch."}

{"answer": "DivisionByZeroError", "explanation": "intdiv(5, 0) throws a DivisionByZeroError, which is a subclass of ArithmeticError in PHP."}

{"answer": "no", "explanation": "The finally block executes regardless of whether an exception was thrown or caught; it always runs."}

{"answer": "no", "explanation": "An exception thrown in a finally block will propagate and can replace or override any exception from the try/catch block, so it does have an effect on the overall result."}

{"answer": "yes", "explanation": "In PHP, casting any object (including an Exception) to bool always results in true."}

{"answer": "no", "explanation": "Shutdown functions registered with register_shutdown_function() are called on normal script termination, but they are NOT called when exit() or die() is invoked."}

{"answer": "no", "explanation": "The 'use' statement only creates a compile-time alias; the class file is loaded (via autoloader) only when the class is actually referenced at runtime."}

{"answer": "function", "explanation": "In PHP, to import a function you use 'use function Namespace\\funcName;', while 'use const' is for importing constants."}

{"answer": "Controller/Api/UserController.php", "explanation": "PSR-4 strips the 'App\\' prefix and converts the remaining namespace segments (Controller\\Api) to directory paths, then appends the class name with .php extension."}

{"answer": "yes", "explanation": "Composer's vendor/autoload.php ultimately calls spl_autoload_register() to register its autoload function with PHP's SPL autoloading mechanism."}

{"answer": "yes", "explanation": "__NAMESPACE__ is a PHP magic constant that returns the fully qualified name of the current namespace (or an empty string if no namespace is defined)."}

{"answer": "no", "explanation": "In PHP, an unqualified class name in 'new' is resolved relative to the current namespace, not the global root; only a leading backslash forces global root resolution."}

{"answer": "yes", "explanation": "PSR-4 maps the namespace 'App\\Model\\User' by stripping the 'App\\' prefix, converting remaining '\\' to '/', and appending '.php', yielding 'src/Model/User.php'."}

{"answer": "yes", "explanation": "PHP allows a use alias inside a function body, and that alias is scoped to that function only."}

{"answer": "yes", "explanation": "In PHP, arrays use value semantics: assignment and function calls copy the array by default (with internal copy-on-write optimization), rather than using reference semantics."}

{"answer": 2, "explanation": "PHP arrays are copied by value on assignment, so appending to $b does not affect $a, which still contains 2 elements."}

{"answer": "yes", "explanation": "In PHP, variables defined in the global scope are not accessible inside a function unless declared with the `global` keyword, accessed via the `$GLOBALS` superglobal array, or passed as parameters."}

{"answer": "no", "explanation": "$GLOBALS['x'] is a direct reference to the global variable, so unset($GLOBALS['x']) removes it globally, not just within that function's scope."}

{"answer": 6, "explanation": "The function increments $x by reference, so $n is changed from 5 to 6."}

{"answer": "yes", "explanation": "In PHP, foreach iterates over the original array using an internal pointer, so appending or modifying elements inside the loop body is visible in the same pass (e.g., new elements added via $array[] will be iterated over)."}

{"answer": "no", "explanation": "A static property belongs to the class itself and is shared among all instances, so changes made through one object are visible in all others."}

{"answer": "no", "explanation": "In PHP, boolean array keys are cast to integers: true becomes 1 and false becomes 0, so the key is stored as an int, not as a bool."}

{"answer": "yes", "explanation": "Since PHP 7.0, a generator can return a value, which is accessible via the Generator::getReturn() method after the generator is complete."}

{"answer": "no", "explanation": "A generator is a one-time iterator; once fully consumed, you must call the generator function again to obtain a new Generator instance rather than calling rewind()."}

{"answer": "yes", "explanation": "In PHP, `yield from` delegates iteration to another generator or iterable, yielding its values as if they were yielded directly by the current generator."}

{"answer": "Generator", "explanation": "Calling a generator function returns a Generator object, and get_class() returns its class name as a string."}

{"answer": 3, "explanation": "The generator yields three values (1, 2, 3), iterator_to_array converts them to an array of 3 elements, and count returns 3."}

{"answer": "no", "explanation": "SplStack implements a LIFO (Last In, First Out) stack, not a FIFO queue; SplQueue is the class that implements a FIFO queue."}

{"answer": "yes", "explanation": "ArrayIterator is an SPL class that wraps an array and implements the Iterator interface, allowing traversal via foreach or explicit iterator methods."}

{"answer": "no", "explanation": "ArrayObject implements IteratorAggregate, so it can be traversed with foreach."}

{"answer": "yes", "explanation": "password_hash() internally generates and embeds a random salt in the returned hash; the function signature has no separate salt parameter."}

{"answer": "no", "explanation": "In PHP 8, PASSWORD_DEFAULT is bcrypt (PASSWORD_BCRYPT), not md5; md5 is not used by password_hash() at all."}

{"answer": "yes", "explanation": "password_verify checks if the plaintext matches the hash; since both use 'secret', it returns true."}

{"answer": "no", "explanation": "strip_tags() removes HTML/PHP tags from a string; SQL injection is protected against by prepared statements/parameterized queries, not by stripping HTML tags."}

{"answer": "yes", "explanation": "session_regenerate_id() is the standard PHP function used to change the session ID after privilege changes like login, preventing an attacker from reusing a known session ID (session fixation)."}

{"answer": "php_sapi_name()", "explanation": "The built-in function php_sapi_name() returns the name of the current SAPI module, such as 'cli' for the command-line interface."}

{"answer": "yes", "explanation": "session_destroy() only removes the session data on the server; the session cookie (PHPSESSID) remains in the browser unless explicitly deleted with setcookie()."}

{"answer": "no", "explanation": "The $_SESSION superglobal is only populated with stored session data after session_start() is called; without it, $_SESSION is simply an empty array."}

{"answer": "never", "explanation": "array_find() is not a built-in PHP function; it is a commonly used user-defined function, so it was not introduced in any specific PHP version."}

{"answer": "yes", "explanation": "PHP 8.4 introduced property hooks, allowing custom get/set logic to be defined directly in the property declaration."}

{"answer": "yes", "explanation": "Asymmetric visibility (e.g. public private(set) string $name) was indeed introduced as a new feature in PHP 8.4."}

{"answer": "8.4", "explanation": "The #[\\NoDiscard] attribute was introduced in PHP 8.4 to indicate that a function's return value should not be discarded by the caller."}

{"answer": "8.4", "explanation": "The pipe operator |> was introduced in PHP 8.4 as part of the Pipe Operator RFC."}

{"answer": "8.4", "explanation": "The clone-with syntax (clone($obj, ['x' => 1]) was introduced in PHP 8.4, released in November 2024."}

{"answer": "8.4", "explanation": "The array_first() and array_last() functions were introduced in PHP 8.4."}

{"answer": 8.5, "explanation": "The RFC Partial Function Application v2 was adopted for PHP 8.5."}

{"answer": "8.4", "explanation": "The clamp() function (RFC clamp_v2) was implemented in PHP 8.4."}

{"answer": "yes", "explanation": "The RFC for Context Managers v2 (providing a 'using' construct for automatic resource cleanup) was adopted into PHP before November 2026."}

{"answer": "yes", "explanation": "The RFC for Bound-Erased Generic Types (generics) was indeed declined, continuing PHP's long history of not yet implementing native generics."}

{"answer": "no", "explanation": "As of late 2026, no RFC making ZTS (Zend Thread-Safe) the default build for PHP has been formally accepted; NTS remains the default distribution build."}

{"answer": "yes", "explanation": "PHP has never shipped built-in runtime generics; even in PHP 8.5 the feature remains absent, with only PHPDoc-level @template annotations available."}

{"answer": "yes", "explanation": "PHP follows a November release cycle; PHP 8.5 would be the latest stable as of early November 2026, with PHP 8.6's GA scheduled for mid-November 2026."}

{"answer": "yes", "explanation": "PHP skipped version 6 and went directly from 5.6 to 7.0 to signal major breaking changes."}

{"answer": "no", "explanation": "The RFC proposing a built-in #[\\Deprecated] attribute was not adopted into PHP core; deprecation is still communicated via docblocks and the trigger_error() mechanism."}

{"answer": "yes", "explanation": "In both Clean and Onion architecture, the dependency rule dictates that inner (core/domain) layers must not reference outer layers; all dependencies point inward toward the center."}

{"answer": "yes", "explanation": "In clean/DDD architecture, domain entities are framework-agnostic PHP classes that depend only on the language itself and possibly the standard library, not on Doctrine or Symfony."}

{"answer": "no", "explanation": "Controllers and Twig templates belong to the presentation (interface) layer, not the business-logic layer; they translate HTTP requests/responses into use-case calls and back, while the business-logic layer contains the use cases themselves."}

{"answer": "Entities", "explanation": "In onion architecture, the innermost layer contains the core domain entities and business rules, which are independent of any framework or external detail."}

{"answer": "yes", "explanation": "Deptrac (and similar tools like PHPMD, ArchUnit for Java) can define layer-dependency rules and automatically fail the build when a forbidden inter-layer call is detected."}

{"answer": "no", "explanation": "A use case (interactor) should be framework-agnostic and persistence-agnostic; accepting an HTTP Request or EntityManager couples it to specific frameworks, violating the dependency inversion principle."}

{"answer": "Repository", "explanation": "In DDD, a Repository provides a collection-like interface for accessing domain aggregates/entities while abstracting the underlying storage mechanism."}

{"answer": "yes", "explanation": "In Clean Architecture the database is an outermost detail behind an interface, so the domain and use-case layers depend only on abstractions and remain unchanged when the underlying database is swapped."}

{"answer": "no", "explanation": "In DDD, an aggregate is a domain-level cluster of objects with a root that enforces invariants; it is a conceptual boundary, not a database table, though it may be persisted across multiple tables."}

{"answer": "yes", "explanation": "By definition in Domain-Driven Design, a Value Object is immutable and its equality is determined by the equality of its field values rather than by object identity."}

{"answer": "Aggregate Root", "explanation": "In Domain-Driven Design, the Aggregate Root is the single external entry point through which all changes to the aggregate must pass."}

{"answer": "yes", "explanation": "In DDD, repositories are declared for Aggregates (via their Aggregate Root), not for every individual entity within the aggregate."}

{"answer": "yes", "explanation": "In Domain-Driven Design, the Ubiquitous Language is the shared vocabulary used consistently by both developers and domain experts to ensure the model, code, and discussions align."}

{"answer": "frame", "explanation": "A frame is the bounded context within which a model and its language maintain consistent meaning, while outside it the same terms refer to different models or interpretations."}

{"answer": "no", "explanation": "DDD recommends a rich domain model where business logic is encapsulated in entities/aggregates, not an anemic model with logic delegated to services."}

{"answer": "yes", "explanation": "In DDD, a Bounded Context ensures each context has its own distinct model, so the same real-world concept (e.g., 'Customer') is represented by different classes with different attributes and behaviors in different contexts."}

{"answer": "yes", "explanation": "Symfony's DI container instantiates services lazily by default, meaning a service object is only created when it is first requested (e.g., via $container->get() or autowiring), not at container bootstrap time."}

{"answer": "debug:router", "explanation": "In Symfony, the console command 'debug:router' (invoked as 'bin/console debug:router') lists all registered routes."}

{"answer": "no", "explanation": "Autowiring's whole purpose is to automatically resolve dependencies based on type hints, so you do NOT need to manually declare every service in services.yaml."}

{"answer": "yes", "explanation": "Twig compiles templates into PHP classes and stores the resulting PHP files in a cache directory so they can be reused on subsequent requests without recompilation."}

{"answer": "yes", "explanation": "Symfony caches the compiled DI container and only rebuilds it when tracked files (e.g., service definitions, config) change, not on every request."}

{"answer": "SYMFONY_ENV", "explanation": "The SYMFONY_ENV environment variable is used to select the active Symfony environment (e.g., dev, prod, staging)."}

{"answer": "no", "explanation": "Symfony's ControllerResolver requires the action method to be public; a private (or protected) method will trigger a ReflectionException, so routing does not work with any arbitrary method of the class."}

{"answer": "no", "explanation": "In Symfony's EventDispatcher, both listeners and subscribers are ordered by the priority parameter they specify, not by whether they are a listener or a subscriber; neither type inherently receives events first."}

{"answer": "yes", "explanation": "Symfony 6.0+ uses the new authenticator system (with AuthenticationEntryPointInterface, etc.) as the primary authentication mechanism, and the old Guard system was deprecated in 6.0 and removed in 7.0."}

{"answer": "IsGranted", "explanation": "The #[IsGranted] attribute from Symfony Security checks whether the current user has a specified role or permission on a controller method, returning a 403 AccessDeniedException if they do not."}

{"answer": "yes", "explanation": "Voters are Symfony's authorization mechanism for object-level access checks, used via isGranted('EDIT', $post)."}

{"answer": "yes", "explanation": "In Symfony 7, Doctrine annotation support was removed; PHP 8 attributes (e.g. #[Assert\\NotBlank]) are the only supported way to declare validation constraints."}

{"answer": "yes", "explanation": "Symfony automatically adds a CSRF token to every form and validates it on submission by default (since Symfony 2.0)."}

{"answer": "yes", "explanation": "Symfony form validation is performed server-side upon form submission, regardless of whether HTML5 client-side validation passed, as server-side validation is the authoritative check."}

{"answer": "make:form", "explanation": "The Symfony MakerBundle command 'make:form' generates a FormType class for building forms."}

{"answer": "no", "explanation": "Symfony stores the user identifier and authentication token in the session, while the password is kept hashed in the database; the plain-text password is never placed in the session."}

{"answer": "yes", "explanation": "In modern Symfony (4+ with Flex), bundle and framework configuration is organized in config/packages/, with one YAML/XML file per bundle or topic (e.g., framework.yaml, twig.yaml, doctrine.yaml)."}

{"answer": "yes", "explanation": "This is a well-known PHP convention (especially in Symfony) where .env holds committed dev defaults and .env.local holds uncommitted local secrets/overrides."}

{"answer": "debug:container", "explanation": "The Symfony command 'bin/console debug:container' lists all registered services and their aliases in the service container."}

{"answer": "no", "explanation": "The Symfony container is frozen once the first service (e.g., the controller itself) is resolved, so calling setParameter() from a controller throws a LogicException."}

{"answer": "no", "explanation": "Since Symfony 4, services are private (public: false) by default; you must explicitly set public: true to fetch them from the container."}

{"answer": "no", "explanation": "Many Symfony bundles work with all-default settings and do not require a dedicated config file in config/packages; a bundle only needs to be registered to function."}

{"answer": "yes", "explanation": "In Symfony, environment variables are referenced in services.yaml (and other config files) using the %env(VAR_NAME)% syntax."}

{"answer": "APP_DEBUG", "explanation": "In Symfony, the APP_DEBUG environment variable (set in .env) enables or disables debug mode, which activates the profiler and Twig's debug features."}

{"answer": "no", "explanation": "Symfony Messenger allows multiple handlers to be registered for the same message class, and all of them will be invoked (ordered by priority)."}

{"answer": "no", "explanation": "The sync transport handles the message immediately in the same process without queuing it for a worker; that's the behavior of async transports."}

{"answer": "php bin/console messenger:consume", "explanation": "In Symfony, the messenger:consume command starts the worker process that pulls and dispatches queued messages from a transport."}

{"answer": "no", "explanation": "In Symfony Messenger, the retry strategy (retry_strategy middleware) is configured per messenger bus, not per transport."}

{"answer": "no", "explanation": "By default, Symfony Messenger uses PHP's native serializer (serialize/unserialize), not JSON."}

{"answer": "yes", "explanation": "Symfony Scheduler schedules tasks at defined intervals and integrates with Messenger to produce and dispatch messages on that schedule."}

{"answer": "Doctrine", "explanation": "Symfony Messenger's Doctrine transport persists messages to database tables using Doctrine ORM."}

{"answer": "yes", "explanation": "Laravel's Messenger pipeline is extensible; you can register custom middleware in the pipeline before or after the built-in middleware such as Dispatchable, Queueable, and SerializesModels."}

{"answer": "yes", "explanation": "Symfony follows a fixed schedule with major releases every two years in May and minor releases every six months in May and November."}

{"answer": "8.4", "explanation": "Symfony 8 requires PHP 8.4 as the minimum version, following the pattern of each major Symfony version bumping the minimum PHP requirement."}

{"answer": "no", "explanation": "Symfony 7.0 removed docblock annotation support entirely; only PHP 8 attributes are supported for validation, routing, etc."}

{"answer": "yes", "explanation": "Symfony's AssetMapper component (7.1+) manages CSS/JS assets on the PHP side using importmap.php for package resolution, without requiring Node.js or webpack."}

{"answer": "no", "explanation": "Symfony 6.4 is a Long-Term Support (LTS) release, receiving 2 years of bug fixes and 3 years of security fixes, unlike regular releases."}

{"answer": "no", "explanation": "Symfony's deprecation policy states that features deprecated in a given major version are removed in the next major version, so upgrading to a new major branch does remove the previous branch's deprecations."}

{"answer": "yes", "explanation": "Symfony follows a long-standing convention of providing UPGRADE files (e.g., UPGRADE-6.0.md) in each component and bundle for every major release to document breaking changes."}

{"answer": "AssetMapper", "explanation": "Symfony's AssetMapper component (introduced in 6.3) manages assets and provides an import-map feature without requiring Node.js or Webpack."}

{"answer": "no", "explanation": "Following Symfony's ~6-month release cadence, by November 2026 the latest would be around Symfony 7.4 or 8.0 at most; 8.2 would not be released until roughly 2027."}

{"answer": "no", "explanation": "Following Symfony's six-month release cycle (Nov/May), Symfony 8.2 is scheduled for May 2026, while November 2026 corresponds to Symfony 8.3."}

{"answer": "8.2", "explanation": "Following standard versioning, the next minor release after 8.1 is 8.2."}

{"answer": "no", "explanation": "Symfony 8.2 is a minor release (x.2), not a major one (x.0); minor releases add features without breaking changes and do not require applications to be rewritten."}

{"answer": "yes", "explanation": "PHP guarantees backward compatibility for minor version upgrades (e.g., 8.1 → 8.2) within the same major version; only major version bumps may introduce breaking changes."}

{"answer": "8.4", "explanation": "The last minor release of Symfony 8.x before Symfony 9.0 is 8.4, following Symfony's pattern of .0 through .4 minor versions per major branch."}

{"answer": "no", "explanation": "Symfony 8.x (including 8.2) requires PHP 8.4 as its minimum version, not PHP 8.5."}

{"answer": "yes", "explanation": "Symfony's deprecation policy guarantees that deprecations introduced in a given major version (8.x) are only removed in the following major version (9.0), so they will not be removed before 9.0."}

{"answer": "no", "explanation": "Twig's {{ }} expressions support a limited subset (variables, method calls, filters, operators) but do not allow arbitrary PHP code like instantiating classes or calling any PHP function directly."}

{"answer": "yes", "explanation": "Twig enables auto-escaping with the 'html' strategy by default to protect against XSS and other injection attacks."}

{"answer": "yes", "explanation": "The Twig |e (escape) filter defaults to HTML context, escaping special characters like <, >, &, \", and ' for safe HTML output."}

{"answer": "number_format", "explanation": "The twig/intl-extra package provides the 'number_format' filter which formats a number according to a specified locale using the PHP Intl extension."}

{"answer": "yes", "explanation": "In Twig, the |raw filter (alias of |safe) marks a value as already safe, preventing the template engine from auto-escaping it."}

{"answer": "yes", "explanation": "In Twig, {{ }} is used to output/print expression values, while {% %} is used for control structures such as if, for, set, etc."}

{"answer": "no", "explanation": "Twig allows you to declare variables inside a template using the {% set %} tag, as well as through loop variables and other built-in constructs."}

{"answer": "dump", "explanation": "The Twig 'dump()' function outputs the debug structure of variables such as arrays and objects."}

{"answer": "yes", "explanation": "Bootstrap is a CSS/JS UI component library, not a Single Page Application framework like React, Angular, or Vue."}

{"answer": "container", "explanation": "The .container class in Bootstrap provides a responsive fixed-width container with a maximum width that changes at each breakpoint (e.g., 540px, 720px, 960px, 1140px, 1320px)."}

{"answer": "no", "explanation": "The Bootstrap grid splits a row into 12 columns, not 16, and modern versions (Bootstrap 4+) use Flexbox rather than CSS floats."}

{"answer": "yes", "explanation": "In Bootstrap 5, the five breakpoints with class-name infixes are sm, md, lg, xl, and xxl (xs is the default and requires no prefix)."}

{"answer": "yes", "explanation": "Bootstrap's spacing utilities like .mt-3 and .px-2 draw from the $spacers map, whose default values are calculated as multiples (or fractions) of the $spacer variable."}

{"answer": "data-bs-toggle", "explanation": "Bootstrap 5 uses the data-bs-toggle attribute to enable interactive components such as dropdowns, collapses, and tooltips on an element."}

{"answer": "yes", "explanation": "Bootstrap 5 removed the jQuery dependency and all its interactive components are built with vanilla JavaScript."}

{"answer": "no", "explanation": "Bootstrap 5.3 enables dark mode with the data-bs-theme=\"dark\" attribute on the <html> element, not a .dark class."}

{"answer": "no", "explanation": "Doctrine ORM does not auto-create tables at runtime; you must explicitly run a schema tool command (e.g., orm:schema-tool:create) or use migrations to generate the database schema."}

{"answer": "persist", "explanation": "EntityManager::persist() schedules a new entity for insertion and marks it as managed without executing SQL until flush() is called."}

{"answer": "no", "explanation": "In Doctrine ORM 3, EntityManager::merge() was removed; you can simply call persist() or work with the entity directly instead of merging a detached instance back."}

{"answer": "yes", "explanation": "DQL (Doctrine Query Language) is an object-oriented query language that references entity class names and their mapped properties rather than raw table and column names."}

{"answer": "null", "explanation": "Doctrine's Repository::find() returns null when no entity with the given ID exists."}

{"answer": "yes", "explanation": "DoctrineBundle registers a kernel.response event listener that automatically calls EntityManager::flush() at the end of each request."}

{"answer": "yes", "explanation": "A managed entity is already tracked by the Unit of Work, so property modifications are detected during change-set computation and committed on flush() without needing persist() again."}

{"answer": "no", "explanation": "In Doctrine ORM, remove() merely marks the entity as 'removed' in the UnitOfWork; the actual SQL DELETE is only issued when flush() is called."}

{"answer": "no", "explanation": "MVCC in PostgreSQL ensures that readers do NOT block writers and writers do NOT block readers; readers see a consistent snapshot while writers can proceed independently."}

{"answer": "EXPLAIN", "explanation": "The EXPLAIN command displays the query's execution plan (how the database will process the query) without actually running it."}

{"answer": "no", "explanation": "SERIAL is a shorthand that creates a sequence and a column DEFAULT, while GENERATED ... AS IDENTITY creates a true identity column with additional semantics (e.g., GENERATED ALWAYS vs BY DEFAULT, different behavior in information_schema, and different ALTER syntax), so they are related but not the same mechanism."}

{"answer": "no", "explanation": "By default, PostgreSQL treats NULLs as distinct from each other in a UNIQUE constraint, so multiple rows can have NULL in that column."}

{"answer": "string_agg", "explanation": "PostgreSQL's string_agg() aggregate function concatenates strings with a specified separator, e.g. string_agg(col, ', ')."}

{"answer": "no", "explanation": "Plain VACUUM only marks dead tuple space as reusable within the table file; it does not shrink the file or return space to the operating system (that requires VACUUM FULL)."}

{"answer": "PARTITION BY", "explanation": "In SQL window functions, the PARTITION BY clause divides rows into groups over which the window function is computed."}

{"answer": "no", "explanation": "READ COMMITTED only prevents dirty reads (reading uncommitted data); non-repeatable reads require the REPEATABLE READ isolation level to be protected against."}

{"answer": "yes", "explanation": "PostgreSQL operates in autocommit mode by default, meaning each individual SQL statement is automatically committed in its own implicit transaction unless an explicit BEGIN/COMMIT block is used."}

{"answer": "COMMIT", "explanation": "The COMMIT SQL command ends a transaction and permanently saves all changes made during that transaction."}

{"answer": "yes", "explanation": "Indexes are used by the database engine to quickly locate rows, so UPDATE and DELETE statements with a WHERE clause on an indexed column also benefit from the index, avoiding a full table scan."}

{"answer": "yes", "explanation": "PostgreSQL supports SAVEPOINT within a transaction, allowing partial rollback via ROLLBACK TO SAVEPOINT without undoing the entire transaction."}

{"answer": "no", "explanation": "EXPLAIN ANALYZE actually executes the query to provide real execution time statistics; plain EXPLAIN shows the plan without executing."}

{"answer": "pgvector", "explanation": "pgvector is the PostgreSQL extension that adds a vector data type and index types (IVFFlat, HNSW) for embedding similarity search."}

{"answer": "yes", "explanation": "A partial index only includes rows that satisfy the specified WHERE condition, so it is indeed built only over those rows."}

{"answer": "no", "explanation": "PostgreSQL implements SERIALIZABLE using Serializable Snapshot Isolation (SSI), which detects serialization anomalies via dependency tracking and aborts a transaction if a cycle is found, rather than locking the rows a transaction reads."}

{"answer": "yes", "explanation": "HTTP 201 'Created' indicates that the request was successful and a new resource has been created as a result."}

{"answer": 204, "explanation": "HTTP 204 No Content indicates a successful request with an empty response body, commonly used after DELETE operations."}

{"answer": "yes", "explanation": "RFC 7231/9110 explicitly classifies DELETE as an idempotent method: issuing the same DELETE request multiple times results in the same server state as issuing it once."}

{"answer": "no", "explanation": "The Access-Control-Allow-Origin header is sent by the server in the response to indicate which origin is allowed to access the resource, not by the client."}

{"answer": "yes", "explanation": "HTTP 429 Too Many Requests (defined in RFC 6585) is specifically used to indicate that a client has sent too many requests in a given time frame, i.e., rate limiting."}

{"answer": "no", "explanation": "It's the opposite: 4xx codes indicate client errors, and 5xx codes indicate server-side errors."}

{"answer": "Content-Type", "explanation": "The Content-Type HTTP header specifies the MIME type of the request or response body."}

{"answer": "yes", "explanation": "RFC 5789 explicitly states that PATCH is not idempotent, whereas PUT is defined as idempotent in the HTTP specification."}

{"answer": "no", "explanation": "Plain == is vulnerable to timing attacks; PHP's hash_equals() should be used for constant-time comparison of password hashes."}

{"answer": "yes", "explanation": "A CSRF token is generated server-side, bound to the user's session, and validated server-side on unsafe (state-changing) requests like POST, PUT, or DELETE."}

{"answer": "Content-Security-Policy", "explanation": "The Content-Security-Policy HTTP header is used to declare a CSP policy that restricts the sources from which a browser can load resources."}

{"answer": "no", "explanation": "OAuth 2.0 is an authorization (not authentication) protocol; the access token represents granted permissions/scopes, while identity is conveyed by an ID token from OpenID Connect."}

{"answer": "no", "explanation": "XSS is primarily prevented by context-aware output encoding when rendering data in the browser, not by input validation before database storage; input validation is a helpful defense-in-depth measure but is not the reliable primary defense against XSS."}

{"answer": "authorization code", "explanation": "In the OAuth 2.0 authorization code flow, the authorization server redirects the user agent back to the redirect_uri with a 'code' parameter (the authorization code), which the client then exchanges for an access token at the token endpoint."}

{"answer": "yes", "explanation": "Refresh tokens in OAuth2 are designed to have a longer lifespan than access tokens and are used to obtain new access tokens without requiring the user to re-authenticate."}

{"answer": "no", "explanation": "A salt does not need to be secret; it is typically stored alongside the hash (e.g., in a database) because its purpose is to ensure uniqueness against rainbow-table attacks, not to provide secrecy."}

{"answer": "no", "explanation": "PHPUnit requires test classes to extend PHPUnit\\Framework\\TestCase; it will not discover or run test methods in arbitrary classes that do not extend it."}

{"answer": "no", "explanation": "setUp() runs before each test method; setUpBeforeClass() is the one that runs once before all tests in the class."}

{"answer": "no", "explanation": "A data provider is specifically designed to let a test run with multiple sets of arguments, not just one."}

{"answer": "expectException", "explanation": "PHPUnit's expectException() method declares an expectation that an exception of a given class will be thrown."}

{"answer": "no", "explanation": "The statement has it backwards: a stub returns predefined data, while a mock verifies that expected methods were called."}

{"answer": "yes", "explanation": "In PHPUnit 10+, the #[DataProvider] attribute is the recommended replacement for the deprecated @dataProvider docblock annotation."}

{"answer": "no", "explanation": "PHPUnit provides the @depends annotation (or depends() method) that allows a test to depend on and receive the return value of another test."}

{"answer": "--random-order", "explanation": "The --random-order PHPUnit command-line option causes tests to be executed in a random sequence."}

{"answer": "3-3", "explanation": "intdiv(7,2) is 3 and intdiv(-7,2) is -3 (truncates toward zero), concatenated as a string gives '3-3'."}

{"answer": -9, "explanation": "In PHP, the exponentiation operator ** has higher precedence than unary minus, so -3 ** 2 is parsed as -(3**2) = -9."}

{"answer": "true", "explanation": "'1e1' and '10' are both numeric strings (scientific notation 1×10¹ = 10), so PHP compares them numerically as 10 == 10, which is true."}

{"answer": "zero", "explanation": "PHP switch uses loose comparison (==), and in PHP 7, 'a' == 0 evaluates to true because 'a' is cast to the integer 0, so the case 0 branch is matched."}

{"answer": "2c", "explanation": "strtr with an array does a single pass; at position 0 both 'a' and 'ab' match, but the longest key 'ab' wins, so it's replaced with '2', leaving 'c' unchanged."}

{"answer": "[]", "explanation": "In PHP 8, substr() returns an empty string when the negative start offset's absolute value exceeds the string length, so the result is '[]'."}

{"answer": "k,n,m", "explanation": "The array union operator (+) keeps left-side values for duplicate keys and appends right-side unique keys, so array_keys yields ['k','n','m'], which implode outputs as 'k,n,m'."}

{"answer": "yxz", "explanation": "usort sorts by index 2, giving order [2,'y',1], [1,'x',2], [3,'z',2]; array_column($a,1) extracts ['y','x','z']; implode yields 'yxz'."}

{"answer": 4, "explanation": "Spreading an array with string keys creates named arguments, so b:1 and a:5 are matched by name, giving $a=5 and $b=1, resulting in 5-1=4."}

{"answer": 3, "explanation": "The first-class callable syntax $p->g(...) creates a closure bound to the object instance itself, not to the variable $p, so setting $p = null does not affect the closure's reference to the object, and $f() still returns 3."}

{"answer": "B", "explanation": "static::class uses late static binding, so it resolves to the actual class of the object (B), not the class where the method is defined (A)."}

{"answer": 10, "explanation": "The setter multiplies the assigned value by 2, so assigning 5 sets the property to 10 (the assignment inside the setter does not recursively invoke the setter)."}

{"answer": "BA", "explanation": "TB::f insteadof TA makes f() return 'B', and TA::f as g aliases TA's f() as g() returning 'A', so the concatenation is 'BA'."}

{"answer": 0, "explanation": "Each class that uses a trait gets its own independent copy of the static property, so setting CX::$n does not affect CY::$n which remains 0."}

{"answer": 2, "explanation": "A return statement in a finally block overrides the return value from the try block, so the function returns 2."}

{"answer": "second", "explanation": "When a finally block throws a new exception, it replaces the original RuntimeException, so the outer catch(LogicException) catches it and prints 'second'."}

{"answer": "App\\Foo|Baz", "explanation": "Baz::class resolves to App\\Foo via the use alias, while \\Baz::class refers to the global Baz class, outputting 'App\\Foo|Baz'."}

{"answer": "noyes", "explanation": "class_exists('Foo') looks in the global namespace (not found, so 'no'), while class_exists('Ns\\\\Foo') finds the class defined in namespace Ns (so 'yes')."}

{"answer": "1,2,99", "explanation": "After foreach by reference, $v remains a reference to the last element $a[2], so assigning 99 to $v changes $a[2] to 99, resulting in 1,2,99."}

{"answer": 3, "explanation": "Static variables in a method are shared per class definition; since B inherits inc() from A, all calls share the same static $n, so after three ++$n calls the value is 3."}

{"answer": 11, "explanation": "send(10) assigns x=10, then return x+1 evaluates to 11, which getReturn() retrieves and echo prints."}

{"answer": "1,2,ok", "explanation": "yield from inner() yields 1 and 2, captures the return value 'ok' into $r, then outer() yields $r, so the full sequence is 1, 2, 'ok'."}

{"answer": "noyes", "explanation": "The hash is created with cost 4, so password_needs_rehash with cost 4 returns false ('no'), and with cost 5 returns true ('yes')."}

{"answer": "strict-out", "explanation": "In PHP 8.5, E_STRICT (2048) is removed from E_ALL, so E_ALL & 2048 equals 0, making the ternary evaluate to 'strict-out'."}

{"answer": "mapped", "explanation": "Symfony's HeaderBag automatically maps HTTP_X_TOKEN server parameter to the X-Token header, so the comparison returns true."}

{"answer": "BCA", "explanation": "Listeners are called in descending priority order: priority 10 (B), priority 5 (C), then default priority 0 (A)."}

{"answer": "same", "explanation": "Doctrine's EntityManager identity map ensures that calling find() with the same ID returns the same object instance, so spl_object_id is equal for both $a and $b."}

{"answer": 0, "explanation": "When persist() is followed by remove() before flush(), Doctrine's UnitOfWork cancels the pending INSERT (the entity's state is REMOVED, so it is excluded from the insert set during computeChangeSets), and since no ID was ever assigned (auto-increment, never actually inserted), the scheduled DELETE is a no-op, leaving the table empty."}

{"answer": 1, "explanation": "COUNT(x) only counts non-NULL values in column x, and there is one NULL row, so the result is 1."}

{"answer": "10,30,60", "explanation": "The window function sum(x) OVER (ORDER BY id) produces running sums 10, 30, 60, and string_agg concatenates them with commas in id order."}

{"answer": "M1M2", "explanation": "Middleware is processed in order: M1 echoes 'M1' then delegates to M2 which echoes 'M2' before reaching the terminal handler, so the output is 'M1M2'."}

{"answer": 11, "explanation": "HandleMessageMiddleware with a HandlersLocator containing multiple handlers for the same message type invokes all of them in sequence, so both closures execute: $n += 1 then $n += 10, yielding 11."}

{"answer": 1, "explanation": "The first INSERT succeeds, the second is skipped by ON CONFLICT DO NOTHING due to the unique index, leaving one row in the table."}

{"answer": 2, "explanation": "Because the UNIQUE constraint is DEFERRABLE INITIALLY DEFERRED, the uniqueness check is postponed until COMMIT, so both INSERTs succeed and the table contains 2 rows."}

{"answer": 6, "explanation": "The --filter test_sum regex matches both test_sum (3 data sets) and test_sum_abs (3 data sets), totaling 6 tests."}

{"answer": "2, 1", "explanation": "The data provider supplies two values (1 and -1), so 2 tests run; the assertion $x > 0 fails for -1, so 1 test fails."}

{"answer": "POST", "explanation": "The -d flag in curl sends data in the request body, which automatically sets the HTTP method to POST."}

{"answer": "GET", "explanation": "The -G flag instructs curl to use the GET method, appending the -d data as a query string to the URL."}

{"answer": "invalid_client", "explanation": "RFC 6749 Section 5.2 specifies that if the client fails authentication (e.g., non-existent client_id), the token endpoint returns the error value 'invalid_client'."}

{"answer": "fragment", "explanation": "In the OAuth 2.0 implicit flow (response_type=token), the access token is passed in the fragment (the part after #) of the redirect URI, so it is not transmitted in the HTTP Referer header."}

{"answer": 6, "explanation": "In Twig, the default filter considers false as empty (via PHP's empty()), so false|default(2) evaluates to 2, and 2 * 3 = 6."}

{"answer": "a3", "explanation": "In Twig, the + operator has higher precedence than ~, so the expression evaluates as 'a' ~ (1+2) = 'a' ~ 3 = 'a3' with no exception thrown."}

{"answer": 0, "explanation": "NotBlank fails only on null, empty string, false, or an empty array (count 0); since [''] has one element it passes, yielding 0 violations."}

{"answer": "Symfony\\Component\\Form\\Exception\\LogicException", "explanation": "Calling isValid() on an unsubmitted form throws a LogicException because a form that has not been submitted can never be valid."}

{"answer": "same", "explanation": "By default, Symfony DI services are shared (singleton), so repeated calls to get() return the same cached instance."}

{"answer": "hi Bob!", "explanation": "The parameters are resolved during compile: 'name' is 'Bob', 'greeting' becomes 'hi Bob', and 'message' becomes 'hi Bob!'."}

{"answer": "960px", "explanation": "At a 992px viewport the lg breakpoint (≥992px) applies, and Bootstrap 5.3 sets .container's max-width to 960px at that breakpoint."}

{"answer": "text-danger", "explanation": "In Bootstrap 5.3's generated CSS, text-danger is defined after text-primary, so with equal specificity the later rule wins the cascade."}

{"answer": 2, "explanation": "The class is in the Domain layer, which may only depend on Domain; using Application\\PlaceOrder and Infrastructure\\Db are two violations."}

{"answer": 3, "explanation": "The Domain class depends on App\\Application\\PlaceOrder (1 violation), App\\Infrastructure\\Db (2nd violation), and App\\Infrastructure\\Logger (3rd violation), since Domain may only depend on Domain."}

{"answer": "10,15", "explanation": "The Money object is immutable (readonly int), so $a retains amount 10 while $c is a new object with amount 15."}

{"answer": 1, "explanation": "The remove method throws before unsetting, so the item 'a' remains in the array, and count() returns 1."}

{"answer": "hi", "explanation": "The code creates an instance of class C, calls the hi() method which returns the string 'hi', and echoes it."}

{"answer": "yesno", "explanation": "Before property access the lazy ghost is uninitialized (prints 'yes'), and after accessing $o->v the object is initialized (prints 'no')."}

{"answer": "no", "explanation": "The Guard authenticator system (including AbstractGuardAuthenticator) was removed in Symfony 6.0, so the class does not exist in Symfony 8.1."}

{"answer": "noyes", "explanation": "In Symfony 8.1, AnnotationClassLoader was removed (deprecated in 6.1, removed in 7.0), while AttributeClassLoader exists, so the output is 'no' followed by 'yes'."}